Transmitting and receiving signals.



RENEWED SEPT. I0 1M5.

Enema 0m. 10,1915.

WITNEBQEQ:

23.4. jaa id @FFTQE.

REGINALD A. FESSENDEN,

MESNE ASSIGNMENTS, TO SAMUEL M. KINTNER, AND HALSEY M. BARRETT, OFBLOOMFIELD,

OF WASHINGTON, DISTRICT OF COLUMBIA,-ASSIGNOR, BY

OF PITTSBURGH, PENNSYLVANIA, NEW JERSEY, RECEIVERS.

TRANSMITTING AND RECEIVING SIGNALS.

Original application filed June 2, 1900, Serial No. 18,878.

Divided and this application filed May 4, 1904, Serial No. 206,392.Renewed Serial No, 53,441. September 10, 1915, Seria1.No. 50,106.

2" 0 all whom it may concern.

I Be it known that I, REGINALD A. Fnssmr- DEN, a citizen of the UnitedStates, resid ng at lVashington, in the District of Columbia,. haveinvented certain new and useful Improvements in Transmitting andReceiving Signals, of which the following is especification.

The invention described herein relates to certain improvements in thetransmission and receipt of electromagnetic waves or impulses-particularly for signaling by wireless telegraphy.

The present invention has for. its object the practical transmission andreceipt of impulses representing signals or messages without mutualinterference of the two operations, and also the transmission andreceipt of independent signal elements during the same'time.

The invention is hereinafter more fully described and claimed.

In theaCcOmpanying, drawings forming a part of this specification I haveshown partly in diagram'apparatus for carrying out my invention.

In the practice of my invention a vertical generating Wire or generatingsurface, 5 ,'is connected at the sending station according to theso-called impulsive type of connection to a terminal or knob it of aninduction coil l Thesecondary coil is connected as usual to bothdischarge terminals of the induction coil and also to ground. Theprimary of the induction coil is in cluded in the circuit of a generator2 and in said circuit is included a circuit make and break mechanism. Aconvenient form of make and break mechanism consists of a metal disk 3mounted upon'a shaft 20'and electrically connected therewith. The shaftis connected to one pole of the generator 2. The disk 3 is provided witha shoulder 22 adapted when the disk is rotatedto strike against theplate 23 connected to the opposite pole of the generator 2. The disk 3is adjustably held in osition-on the shaft and may be clamped in anydesired position.

By rotation of the shaft the circuit of the generator will be made'andbroken at each rotation. As the periodicityof the magnetic Waves isdependent upon the self-induction Specification of 'Letters Patent.

Patented Oct. 19, 1915. Divided and application ifiled March 29} 1901,

multiplied by the capacity and as self-induction and capacity of thesending wire vary with the length and the diameter of the \vire, thelatter is so proportioned, as by varying its length as .to give thedesired periodicity.

he receiver at the distant station is essentially like the transmitterand its receiving Wire is adjusted to have substantially the sameperiodicity as the sending wirec'. 0., the wire or generating surface atthe receiving station and the corresponding wire at the sending stationhave the same value of the quantity self-induction multiplied by thecapacity. The tuning of this pair-of wires may be'done conveniently byslightly varying the length or diameter 'of one of them. The mechanismcontrolled or operated by the voltages or current induced in the reknownin the art,-that the recording or indicating mechanism connected to thereceiving wlre will be acted on or operated only by the voltages orcurrents induced by the magnetic waves from the correspondingwire atthev sending station. As for example, the indicating mechanism connectedto the receiving wire 5 will not be acted on or operated by any voltagesor current other than that induced by magnetic waves generated by thesending wire 5.

Any suitable form or construction of mechanism may be employed forrecording or indicating the signals received. As for example, thecoherer 2% arranged in the circuit of the grounded receiving wire.-

This coherer is also included'as is customary in circuit 25* from agenerator 26, said circuit also including portions of the recording orindicating mechanism 33. The re cording mechanism or other indicator maybe of any preferred type.

In lieu of a coherer, mechanism may be employed for transforming thecurrent or voltages induced by the magnetic waves into energy of motionas shown and described in Patent Number 706,735. This mechanism is acurrent operated, low resistance, cumulatively acting, constantlyreceptive, receiver adapted to transform the energy of the receivedelectromagnetic waves directly into the energy of motion. In the drawingis shown a form of such mechanism, which consists of a coil 7 in serieswith the receiving wire and a ring or element 8 so sup- 5 ported in thecoil that a plane at right an-- gles to the aXis of the ring or elementwill be at an angle oit' approximately with a plane at right angles tothe axis of the coil.

This ring is balanced on knife edges or supv 15 tion of the ring willnormally rest lightly thereon. This microphoniccontact, the element 8and the conducting pivotal support 13 for the latter, form parts of acircuit from a generator 15. The indicating mech- 2o anism may bedirectly or indirectly controlled by the circuit of generator 15.

As the wire or'suniace 5 at one'station may be employed both forgenerating and receiving the magnetic waves, as signals are 2:; sent orreceived, the indicating or receiving mechanism and the generatingmechanism are connected to said wire or surface as shown in the drawing.in order to protect the indicating or receiving mechanism when assending messages, a switch mechanism is interposed between the wire orsurface '5 and said indicating mechanism.- A convenient form orconstruction of such switch consists of a cylinder 4:3 of insulatingmaterial 3% mounted on the shaft and metal springs 44 bearing on thecylinder. A metal band is placed on the cylinder in line with thesprings 44c, said band extending around the cylinder except for adistance a little to greater than the peripheral length of the knob onthe disk 3 of the circuit breaker. The band 45 is so arranged that thesprings a l will not be in contact with the band when the knob 22 is incontact with the cuit of the transmitting mechanism and at thecorresponding period the receiving mechanism will be cut out by thebreak and M make of the switch 44, l5. Obviously I am enabled by meansof the above apparatus to signal by generating electrical impulses andto render the receiver unresponsive during the time of such generationand to receive impulses by rendering the receiver sensitive alternatelyto association with the senei g and receiving apparatus while sending,the

.paratus being too short to permit int 'trical si ;nals, each signalconsisting a groups in the train, and rendering sa during the time whenthe sending impuises are not being emitted and to cause such conditionsto succeed each other so rapidly practically to effect simultaneoustransmission and reception of signals. yo I This application is adivision of my prior application Ser. No. 53,441, filed March 29, 1901,{now Patent No. 'ZZ'LOM) which a division of an earlier application rice18,878, tiled June 2, 1900, which latter ap plication has resulted inPatent No. 'Yili'fifiii.

What I claim and desire to, secure by Iii-ct ters' Patent is: i

1. In the art of electric signaling. the method of sin'iultanconslysending ant receiving signals which comprises rendering the receiver atthe sending station alter nately responsive and unresponsiveperiod callywhile sending, the period of interrup tion being too short to interferewith the re ceived signals and the receiver bei sponsive during theintervening non-tench intervals. 7 i

2. In wireless telegraphy, the method of simultaneously sending andreceiving mes sages which comprises shifting the antenna )GIlOClS ofinterru tion of the recei ii; an

ence with signals composed of trains of rate groups of waves, and thesignal sent occupying the interval of interruption, substantially asdescribed.

3. In the art oi "wireless signaling, 11cc method which consists'intransmitting elec train of rapidly succeeding groups 0. pulses, andrendering the receiver a; sending station unresponsive during M19 timesof gene ation of such groups impulses in the train, while leaving itresponsive during the time intervals between the separate groups in atrain.

a. In the art of wireless signaling, ti" method which consists ingenerating sigmal consisting each of a train of separate group oielectromagnetic waves, and cutting on he sensitive member of a receivingratus at the sending station during the time of actual generation ofeach group,arnd cut ting the same in during the intervals between timesof generation. v

5. In the art of wireless signaling, the method which consists ingenerating a train of separated groups of electric impulses t form asignal, and renderinga receiver at the sending station insensitiveduring the times of such generation of l ceivcr sensitive during theintervening time intervals. i

G. In the art method which consists generating rapid succeeding separategroups of electric int of Wireless signaling the fir .pulses, renderinga receiver at the sending station insensitive durin the time of gener-,'ation of each group an rendering said receiver sensitive during all theintervening times.

7. The method of simultaneously transmitting and receiving signals byelectromagnetic waves which comprises sending a multiple-group of wavesof definite and high frequency, a train of such groups constituting asignal and altering the operative relation of a normally sensitivereceiver to the antenna at the sending station to make itinsensitiveonly during the actual time of sending each group of waves.

8. In Wireless signaling the method of sending signals each consistingof a train of separated and rapidly succeeding groups of electricimpulses and meantime altering the operative relation to the antenna ofa receiver at the sending station so that it is insensitive during thetimes of sending each group, and sensltive inthe intervals between themultiple groups of impulses forming the signal.

9. In the art of Wireless signaling, the

method of simultaneously sending and receiving messages, Which comprisestransmitting signals composed ofelelnents, each element comprising anumber of groups of impulses, and each impulse comprising. a number'ofhigh frequency oscillations, and rendering a receiver at thesendingstation un-' responsive during thetime of actual emis sion ofeach group of the elements, While leaving it responsive durin'g theintervening time intervals. I

REGINALD A. FESSENDEN.

Witnesses: I

THOMAS PZ'BURNE, JESSIE E. BENT.

